Water-soluble basic azo dyestuffs

ABSTRACT

WATER-SOLUBLE BASIC AZO-DYESTUFFS CONTAINING AN AMINONIUM-ALKANOYL RADICAL BOUND TO AN AMINOAPHTHALENE COUPLING COMPONENT.

United States Patent US. Cl. 260-156 12 Claims ABSTRACT OF THEDlISCLDSURE Water-soluble basic azo-dyestuffs containing anammonium-alkanoyl radical bound to an aminonaphthalene couplingcomponent.

The present invention provides Water-soluble basic azo dyestuffs freefrom acidic groups imparting solubility in water, especially sulphonicacid or carboxylic acid groups, which correspond to the formula in whichA represents the residue of a diazotized amine and B represents theresidue of a coupling component, and in which at least one of theresidues A or B is derived from an aminonaphthalene containing a groupof the formula attached to the naphthalene nucleus, in which formula alkrepresents an alkylene group, R R and R each represent an alkyl, aralkylor cycloalkyl radical, and R R and R may, together with the nitrogenatom, form a heterocyclic ring, and X represents an anion.

The invention also provides a process for the manufacture ofwater-soluble basic azo dyestulfs of the above formula, wherein -(a) adiazotized amine is coupled with a coupling component, at least one ofthe components being an aminonaphthalene containing a group of theformula attached to the naphthalene nucleus, in which formula R R R andX have the meanings given above, or (b) an azo dyestutf, the diazoand/or coupling component of which is derived from an aminonaphthalenecontaining a halogenated acyl group attached to the naphthalene nucleus,is reacted with a tertiary amine of the formula or (c) an azo dyestutfin which at least one of the residues of the diazo component andcoupling component is derived from an aminonaphthalene containing agroup of the formula is treated with a quaternizing agent.

The amino group in the aminonaphthalenes to be used in method (a) may besubstituted, for example, by one or two alkyl groups or a phenyl group.The aminonaphthalenes preferably correspond to the formula ice in whichR R and R have the meanings given above and n stands for l or 2. Thesecompounds are obtainable by condensing an acylated or dialkylatedaminonaphthalene with chloracetyl chloride or chloropropionyl chloridein the presence of aluminium chloride, reacting the chloracetyl compoundso obtained with the appropriate tertiary amine and, if necessary,splitting off the N-acyl group. The following starting materials may bementioned as examples: l acetylaminonaphthalene, 2acetylaminonaphthalene, N-acetyl-l-ethylaminonaphthalene,N-acetyl-l-methylaminonaphthalene, N-acetyl-l-phenylaminonaphthalene,N-acetyl-Z-ethylaminonaphthalene, N-acetyl-Z-phenylaminonaphthalene and2-diethylaminonaphthalene.

The aminonaphthalenes containing the residue of the formula to be usedin accordance with the invention may be used both as diazo and couplingcomponents. In the former case it is natural that only aminonaphthaleneshaving a primary amino group are used. Subsequent to diazotization, theycan be coupled with any desired coupling component, for example, withthose of the benzene or naphthalene series or with those of theheterocyclic series. Of the coupling components of the benzene series,special mention may be made of the aminobenzenes, for example,dimethylam'line, diethylaniline, N-ethyl-N-cyanoethylaniline,di-(cyanoethyl -aniline, di hydroxyethyl -aniline, di-(cyanoethoxyethoxy)-aniline, N-ethyl-N-phenylaniline or diphenylamine.Of the coupling components of the naphthalene series, mention may bemade, for example, of 1- or 2-naphthylamine and also2-phenylaminonaphthalene. Suitable heterocyclic coupling components are,for example, the indoles, for example, Z-methylindole,2,5-dimethylindole, 2,4-dimethyl-7-methoxyindole,Z-methyl-S-ethoxyindole, 2- methyl-S- or -6-chloroindole,1,2-dimethylindole, l-methyI-Z-phenylindole, Z-methyl-S-nitroindole,2-methyl-5-cyanoindole, 2 methylchloroindole, 2-methyl-5,7-dichloroindole or Z-phenylindole, l-cyanoethyl-2,6-dimethyl-indoline, and alsopyrazoles, for example, l-phenyl-S-aminopyrazole or3-methyl-pyrazolone-5 or 1-phenyl-3-methylpyrazolone-5, quinolines, forexample, 1-methyl-4-hydroxyquinoline-2 or pyrimidines, for example,barbituric acid.

When aminonaphthalenes containing the residue of the formula are used ascoupling components, the diazo components used may be any diazotizablearomatic or heterocyclic amines. Aromatic amines that may be mentionedare, for example, aminonaphthalenes, but especially aminobenzenes. Thesepreferably correspond to the formula in which X represents a hydrogen orhalogen atom, a cyano, carbalkoxy or alkylsulphonyl group, asulphonamide or phenylazo group which may be substituted or a nitrogroup, Y represents a hydrogen or halogen atom or a nitro group, analkyl group, an alkoxy group, a trifluoromethyl group, a carbalkoxygroup or a cyano group and Z represents a hydrogen or halogen atom, andin which at least one of the residues X and Y represents a nitro group,a carbalkoxy group, a cyano group, an alkylsulphonyl group or aphenylazo group.

The following aminobenzenes may be mentioned as examples:

1-amino-4-chlorobenzene, 1-amino-4-bromobenzene,1-amino-4-methylbenzene, 2-amino-5-nitrol-phenylmethylsulphone,1-amino-4-nitrobenzene, l-amino-4-cyanobenzene,4-amino-3-chloro-l-phenylmethylsulphone, 1-amino-2,S-dicyanobenzene,1-amino-4-carbalkoxybenzene, 1amino-2,4-dichlorobenzene,1-amino-2,4-dibromobenzene, 1-amino-2-methyl-4-chlorobenzene,1-amino-2-trifluoromethyl-4-chlorobenzene,1-amino-2-cyano-4chlorobenzene, 1amino-2-cyano-4-nitrobenzene,l-amino-Z-carbomethoxy-4-chlorobenzene,1-amino-2-carbomethoxy-4-nitrobenzene, 1-amino-2-chloro-4-cyanobenzene,1-amin0-2-chloro-4-nitrobenzene, 1-amino-2-chloro-4-carbethoxybenzene,1-amino-2,4-dinitrobenzene, 1-amino-2,4-dicyanobenzene,1-amino-2,6-dichloro-4-cyanobenzene,1-amino-2,6-dichloro-4-nitrobenzene, l-amin-2,4-dicyano-6-chlorobenzene,1-amino-2,4-dinitro-6-chlorobenzene, 4-amino-3-chlorobenzenesulphonicacid dimethylamide, 4-amino-3,5-dichlorobenzenesulphonic aciddimethylamide, 4-amino-2,S-dichlorobenzenesulphonic acid dimethylamide,4-aminobenzene, 4-amino-2-chloroazobenzene,4-amino-2,4-dichloroazobenzene, 4-amino-3'-chloroazobenzene,4-amino-2'-nitrazobenzene, 4-amino-3-nitrazobenzene,3-amino-3'-nitrazobenzene, 4-amino-Z-methylazobenzene,4-amino-4-methoxyazobenzene, 4-amino-3-nitro-2-chlorazobenzene,4-amino-3-nitro-4'-chlorazobenzene,4-amino-3-nitro-2,4-dichlorazobenzene and4-amino-3-nitro-4'methoxyazobenzene.

Suitable heterocyclic diazo components are, for example,2-aminothiazole, preferably Z-amino-S-nitrothiazole, or especiallyZ-amino-benzthiazoles, for example, Z-aminothiazole,2-amino-5-nitrothiazole, 2-amino-5-cyanoth1azole,2-amino-4-methyl-5-nitrothiazole, 2-amino-4-methylthiazole, 2 amino 4phenylthiazole, 2 amino-4-(4- chloro) phenylthiazole, 2amino-4-(4-nitro)-phenylthiazole, 2 aminobenzthiazole, 2amino-6-methylbenzthiazole, 2 amino 6 -methoxybenzthiazole, Z-amino-6-chlorobenzthiazole, 2 amino 6-nitrobenzthiazole, and also 2amino-1,3,4-thiadiazole, 2-amino-1,3,5-thiadiazole and2-amino-4-phenyl-1,3,5-thiadiazole.

Diazotization of the above-mentioned diazo components may be efifectedby known methods, for example, with the aid of a mineral acid,especially hydrochloric acid, and sodium nitrite.

Coupling may likewise be carried out in known manner, for example, in anacid to alkaline medium, if necessary, in the presence of sodium acetateor some similar bufier or catalyst which influences the rate ofcoupling, for example, pyridine, or the salts thereof.

In method (b) of the present process a dyestuff containing a halogenatedacyl group is reacted with a tertiary amine, for example,trimethylamine, triethylamine, triethanolamine, dimethylcyclohexylamine,N-methylpiperdine or pyridine, advantageously by heating in an excess ofthe amine in the presence or absence of a solvent. The dyestulfcontaining a halogenated acyl group is advantageously obtained bycoupling a diazotized amine with a coupling component, whereby at leastone of the components is an aminonaphthalene containing a halogenatedacyl group attached to the naphthalene nucleus.

The starting materials used in method (c) of the present process is adyestufl in which preferably R and R are alkyl radicals. This is treatedwith an alkylating agent, advantageously with an alkyl or aralkyl halideor an alkyl or aralkyl ester of sulphuric acid or an organic sulphonicacid. Examples of alkylating agents are methyl chloride, methyl bromide,methyl iodide, benzyl chloride, trimethyloxonium boron fluoride,dimethyl sulphate, diethyl sulphate, benzene-sulphonic acid methyl esterand para-tolucue-sulphonic acid ethyl or butyl ester. Alkylation isadvantageously carried out by heating in an inert organic solvent, forexample, a hydrocarbon, for example, carbon tetrachloride,tetrachloroethane, chlorobenzene, ortho-dichlorobenzene, ornitro-hydrocarbons, for example, nitromethane, nitrobenzene ornitronaphthalene. It is also possible to use acid anhydrides, acidamides or nitriles, for example, acetic anhydride, dimethylformamide oracetonitrile, or also dimethylsulphoxide. Use can also be made of anexcess of alkylating agent instead of an inert solvent. In this case,care must be taken to ensure that the mixture does not heat upexcessively, because the reaction is highly exothermic. In most cases,however, especially in the presence of an organic solvent, it isnecessary to apply external heat to the reaction mixture in order toinitiate the reaction. In special cases, alkylation may also beperformed in an aqueous medium or with the use of an alcohol, possiblyin the presence of a small amount of potassium iodide.

Purification of the dyestulf salts is advantageously effected bydissolving them in water; any unreacted dyestufl used as startingmaterial can then be removed as insoluble matter by filtration. Thedyestuff can be precipitated from the aqueous solution by the additionof a Water-soluble salt, for example, sodium chloride.

The dyestuifs obtainable by the process of the invention preferablycontain as anion the residue of a strong acid, for example, sulphuricacid, or the semi-esters thereof, or the residue of an arylsulphonicacid, or a halogen ion. The above-mentioned anions introduced into thedyestufi molecule in accordance with the invention may also be replacedby anions of other inorganic acids, for example, by anions of phosphoricacid or sulphuric acid, or by anions of organic acids, for example,those of formic acid, acetic acid, chloracetic acid, oxalic acid, lacticacid or tartaric acid; it is also possible to use the free bases incertain cases. The dyestuff salts may also be in the form of doublesalts, for example, with halides of elements of Group II of the PeriodicTable, especially zinc or cadmium chloride.

The dyestuif salts obtained by the process of the invention are suitablefor dyeing and printing a very wide variety of materials, for example,tannin-treated cellulosic fibres, silk, hair, leather, and also fullysynthetic fibres, especially polyacrylonitrile and polyvinylidenecyanide (Darvan). Dyeings produced oin these fibres are distinguished bya very good fastness to light. The dyestufis are also capable ofensuring good reservation of wool, which makes them specially suitablefor the dyeing of union f-a'brics made from wool and polyacrylonitrilefibre. Also worthy of mention is the fact that the dyeings obtaineddisplay a good fastness to carbonizing.

The present invention also includes the starting materials containing aternary nitrogen atom corresponding to the quaternated dyestuffsprepared in accordance with method (0) and which are primarily suitablefor use as disperse dyestuffs in the dyeing of cellulose acetate fibres,and especially fully synthetic polyester fibers, for exampple,polyethylene terephthalate fibers.

The following examples illustrate the invention. Unless otherwisestated, the parts and percentages are by weight.

EXAMPLE 1 25 parts by volume of a solution of 2.79 parts of a mixture of1-amino-4-, and -8-[a-(N-chlorotrimethylamino)-acetyl]-naphthalene inhydrochloric acid are diazotized with parts by .volume of an N-sodiumnitrite solution. The solution so obtained is run into a mixture of 1.6parts of N-methyl-N-2-cyanoethylaniline, 50 parts by volume of ethylalcohol and 50 parts of ice, and the reaction mixture is renderedneutral to Congo paper by the addition of sodium acetate. Aftercoupling, the dyestuif is precipitated by the addition of sodiumchloride, isolated by filtration and dried. It dyes polyacrylonitrilefibres fast, red-orange tints.

The mixture of l-amino-4-, -5- and -8-[a(N-Chl0l0trimethylamino)-acetyl]-naphthalene is prepared as follows:

18.5 parts of l-acetylaminonaphthalene are stirred into 125 parts byvolume of carbon disulphide and then 47 parts of aluminum chloridepowder are added quickly. parts of chloracetyl chloride are added to themixture at 20 to C. in the course of one hour dropwise and the batch issubsequently heated for 2 to 3 hours at 40 to 45 C. until the evolutionof hydrochloric acid is finished. The carbon disulphide is poured 01f,the viscous brown mass which remains is decomposed with ice, and thechloracetyl compound which is obtained in a good yield is isolated byfiltration.

26.2 parts of the chloroacetyl compound are introduced into a mixture of50 parts by volume of acetone and 50 parts by volume of water and then25 parts by volume of a 4 N aqueous trimethylamine solution are added.The batch is stirred for 6 hours at 20 to 25 C. and then for 2 hours atC., diluted with 100 parts by volume of water, the acetone is allowed toevaporate, 50 parts by volume of concentrated hydrochloric acid areadded and the solution is boiled for 1 hour under reflux. The solutionso obtained can be used as it is in the manufacture of the dyestuffs.

A mixture of 2-amino-6- and-8-[a-(N-chlorotrimethylamino)-acetyl]-naphthalene can be obtained in ananalogous manner from 2-acetylamino-naphthalene.

Similar new diazotization or coupling components are obtainable when thetrimethylamine is replaced by an equivalent amount of triethylamine,dimethylamine, N- methylpiperidine or pyridine.

By using in Example 1 the coupling components indicated in Column II ofTable 1 below instead of N- methyl-N-Z-cyauoethylaniline, basicdyestutfs are obtained which dye polyacrylonitrile the tints listed inColumn HI.

TABLE 1 I II III Coupling component Tint 1 Z-methylindole Orange. 23-methy1pyrazolone- (5) Yellow.

3-- Z-naphthylamine Red. 4 Diphenylamine Orange 5. Barbituric acidYellow 6. 1,3,S-trimethyl2-methylene-indolenine Orange. 7Indane-1,3-dione Do.

EXAMPLE 2 6 mixture is rendered neutral to Congo paper by the gradualaddition of sodium acetate. The dyestuff which precipitates subsequentto coupling is isolated by filtration and dried. It dyespolyacrylonitrile fibres fast, red-brown tints when applied in the formof an aqueous solution.

Brown dyeings are likewise obtained by using 2,4-dinitraniline or2,6-dichloro-4-nitraniline instead of 4-nitraniline.

EXAMPLE 3 2.79 parts of a mixture of 2-arnino-6- and -8-[oc-(N-chlorotrimethylamino -acetyl] naphthalene are diazotized in the mannerdescribed in Example 1. The diazo solution so obtained is run into anice-cold neutral solution of 2.23 parts of Z-Haphthylamine-l-sulphonicacid while stirring, and the coupling mixture is kept neutral to Congopaper by the addition of sodium acetate crystals. The dyestuff whichprecipitates subsequent to coupling in the form of dark red grains dyespolyacrylonitrile fibres clear, orange tints.

By using the coupling components listed in Column II of Table 2 belowinstead of 2-naphthylamine-l-sulphonic acid, dyestuffs are obtainedwhich yield the tints listed in Column III.

EXAMPLE 4 The procedure described in Example 2 is followed, but thecoupling component used is a mixture of 2-arnino-6- and -8- [a-N-chlorotrimethylamino -acetyl -n aphthalene. After coupling, thedyestuff is salted out with sodium chloride, isolated by filtration anddried. It dyes polyacrylonitrile fibres fast-to-light scarlet tints whenapplied in an aqueous bath.

Further dyestufis which produce the tints listed in C01- umn III ofTable 3 below are obtained when the 4-nitraniline is replaced as diazocomponent by the compounds listed in Column II.

TABLE 3 I II III Diazo component Tint 1 2-chloro4-nitraniline Red.

2 2-methoxy-4-nit1'aniline Do. 3- 2 rnethoxy-fi-nitraniline Orange 42,4-dinitraniline Violet 5.. -eyano-4-nitianiline Claret 6.-ammo-6-ethoxybenzthiazole Do. 7- 3-trifiuoromethylaniline Yellow 8laminoQA-dinitro-6-ehlorobenzene Violet.

. 4-aminobenzoie acid-2-methoxyethylester Orange. 10.4-amino-3phloro-l-pheuylmethylsulphone 0. 11. l-arninonaphthaleneYellowbrown.

12 2,6-dichloro-4-nitraniline Red. l3. laminoazobenzene Red. l4Q-amino-fi-nitrodiphenylether Red. l52-amino-5-nitro-4-chlorodiphenylether Red. l62-amino-5-nitro-l-phenylmethylsulphone Violet. 17 2amino-5-nitrothiazoleBlue.

EXAMPLE 5 1.82 parts of 2-chloro-nitraniline are diazotized in the usualmanner and coupled with a hydrochloric acid solution containing 2.87parts of a mixture of 2-amino-6- and -8-]ot-(N-chloropyridino)-acetyl]-naphthalene. The mixture is rendered neutral to Congo paper by theaddition of sodium acetate and the dyestufi? is precipitated by theaddition of sodium chloride. The dyestuff yields red dyeings possessinggood properties of fastness on polyacrylonitrile fibres.

EXAMPLE 6 4.14 parts of 2,6-dichloro-4-nitraniline are diazotized innitrosyl hydrogen sulphate and the diazo compound so obtained is addeddropwise to a hydrochloric acid solution of 4.4 parts of a mixture of2-amino-6- and -8-chloroacetylnaphthalene which is cooled with ice. Thebatch is rendered neutral to Congo paper by the slow addition of aqueoussodium acetate solution, the water-soluble dyestuff is isolated byfiltration, washed well with water and dried.

4.37 parts of the dyestutf so obtained which contains a chloroacetylgroup are stirred with 10 parts of pyridine for 1 hour at 120 C. until atest sample is completely soluble in water. The batch is diluted with100 parts of water and the dyestuff is precipitated by the addition of10 parts of sodium chloride. It dyes polyacrylonitrile fibers fast,red-brown tints.

Dyestuffs having similar dyeing properties are obtainable when thepyridine is replaced by the same amounts of N-methylpiperidine orN-methylmorpholine.

Basic dyestuffs yielding the tints indicated in Column IV in Table 4below are obtained in an analogous manner by coupling the diazo compoundof an amine listed in Column II with the mixture of 2-amino-6- and -8-chloroacetylnaphthalene and then efiecting reaction with a tertiary baselisted in Column III.

EXAMPLE 7 Using Z-acetylaminonaphthalene as starting material, the sameprocedure is followed as in Example 1 for the manufacture of theintermediate product, but replacing the trimethylamine with anequivalent amount of dimethylamine solution. Subsequent to acidichydrolysis, a solution is obtained containing the mixture of 2-amino-6-and -8-(a-dimethylamino)-acetylnaphthalene. 70 parts by volume of ahydrochloric acid aqueous solution containing 6.84 parts of the abovemixture are diazotized by the addition of 7.5 parts of a 4 N sodiumnitrile solution while cooling with ice, and the diazo solution iscombined at C. with a solution of 5.97 parts ofN,N-bis-2-cyanoethylaniline in 100 parts of dimethylformamide. Themixture is rendered neutral to Congo paper by the addition of sodiumacetate, stirred for several hours and then diluted with 500 parts ofwater. The dyestutf which precipitates is isolated by filtration, washedwith water and dried. 8.76 parts of the brown dyestuff powder soobtained, 200 parts of chlorobenzene and parts of dimethyl sulphate arestirred for 6 hours at 110 C., 200 parts of water are added, and thechlorobenzene is removed with steam. The dyestufi is precipitated out ofthe aqueous solution by the addition of sodium chloride. It dyespolyacrylonitrile fibres strong, orange tints possessing a good fastnessto light.

Fast, reddish yellow dyeings are obtained by using l,2- dimethylindoleinstead of N,N-bis-2-cyanoethylaniline.

EXAMPLE 8 7,54 parts of the dyestutf obtained by coupling diazotized4-nitraniline with a mixture of 2-amino-6- and -8-(0-dimethylamino)-acetylnaphthalene are dissolved in 200 parts ofchlorobenzene and the solution is then heated for 10 hours at 130 C.together with 2.6 parts of benzyl chloride. The chlorobenzene is thenremoved by steam distillation, the aqueous mixture which remains isfiltered while hot to remove any unreacted dyestutf, and then thedyestulf is precipitated from the clear solution by the addition of asmall amount of sodium chloride. It dyes polyacrylonitrile fibresscarlet tints possessing excellent properties of fastness.

A- dyestutf which is identical with the one described in Example 4 isobtained when quaternation is efiected with dimethyl sulphate instead ofbenzyl chloride.

Dyeing prescription 1 part of the dyestuff obtained in the mannerdescribed in the first paragraph of 'Example 1 is dissolved in 5,000parts of water in the presence of 2 parts of acetic acid of 40%strength. parts of dried polyacrylonitrile staple fibre yarn are enteredinto the dyebath so prepared at 60 C., the temperature is raised to 100C. in the course of 30 minutes, and dyeing is carried out for one hourat the boil. The yarn is then well rinsed and dried. A red-orange dyeingpossessing a very good fastness to light, to sublimation and to washingis obtained.

What is claimed is:

1. An azo-dyestulf of the formula in which R and R each represents amember selected from the group consisting of lower alkyl, hydroxy-loweralkyl, phenyl-lower alkyl and cyclo-lower alkyl, R represents loweralkyl or hydroxy-lower alkyl; R and R taken together with the nitrogenatom represent a member selected from the group consisting of anunsubstituted or lower alkyl-substituted piperidine, morpholine orpyrrolidine ring and R R and R taken together with the nitrogen atomrepresent an unsubstituted or loweralkyl-substituted pyridinium ring, Xrepresents an anion of a strong inorganic acid, of a sulfuric acidsemi-ester, of a carboxylic acid or of a sulfonic acid, It is 1 or 2 andA represents a benzene of the formula in which X, is a member selectedfrom the group consisting of hydrogen, chlorine, bromine, cyano, lowercarbalkoxy, lower alkyl-sulfonyl, sulfonamide, 'N-lower al kylsulfonamide, nitro, phenylazo, nitrophenylazo, chlorophenylazo, loweralkylphenylazo and lower alkoxyphenylazo, Y is a member selected fromthe group consisting of hydrogen, chlorine, bromine, nitro, lower alkyl,lower alkoxy, trifiuoromethyl, lower carbalkoxy and cyano and Z is amember selected from the group consisting of nitro, lower carbalkoxy,cyano, lower alkylsulfonyl, hydrogen, chlorine and bromine.

21. An azo-dyestuff as claimed in claim 1 of the formu a OGHg-R in whichY; represents a member selected from the group consisting of hydrogen,chloro, bromo, nitro, methylsulfone and cyano, Z is a member selectedfrom the group consisting of hydrogen, chloro and bromo and R is amember selected from the group consisting of /CH2O\H\1 /CHCH I\ CH -l CHI( zHs)a X- crrrol X- CH=C X- and wherein X- is selected from the groupconsisting of an anion, of a strong inorganic acid, a sulfuric acidsemiester, a carboxylic acid and a sulfonic acid.

3. The azo-dyestuif as claimed in claim 1 of the formula wherein one Zis hydrogen and the other Z is 4. The azo-dyestuff as claimed in claim 1of the formula wherein one Z is hydrogen and the other Z is x- -c oorigin- 0H,

5. The azo-dyestuff as claimed in claim 1 of the formula wherein one Zis hydrogen and the other Z is 6. The azo-dyestufi as claimed in claim 1of the formula 1 OzNQN=N C H; Z

wherein one Z is hydrogen and the other Z is 7. The azo-dyestuff asclaimed in claim 1 of the forwherein one Z is hydrogen and the other Zis Xi COCH N+-(CH;)

9. The azo-dyestufi as claimed in claim 1 of the formula 10. Theazo-dyestufi as claimed in claim 1 of the formula Cl Z- wherein one Z ishydrogen and the other Z is 11. The azo-dyestuff as claimed in claim 1of the formula wherein one Z is hydrogen and the other Z is 12. Theazo-dyestuff as claimed in claim 1 of the formula References CitedUNITED STATES PATENTS CHARLES B. PARKER, Primary Examiner D. M. PAPUGA,Assistant Examiner US. Cl. X.R.

810, 13, 177, 179; 260146 D, 152, 154, 155, 158, 162, 15 165, 184, 191,194, 196, 294.7 I, 429 R, 429.9, 459, 501.15,

CASE 585l/E @2 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 3,631,16H Dated December 28,1971

Inventor(s) GERT HEGAR It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

q Column 9, line 32, "X" should read X" Column 10, line 64, "Cl" shouldread Cl Column 11, lines 13-15, the right-hand side of the formulashould read:

H H C--C -cocH N CH \H H/ C=C Cl Signed and sealed this 8th day ofAugust 1972.,

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents

